Spraying apparatus



Patented May I, 1934 4' SPRAYING APPARATUS Orrick H. Biggs', Beverly, and Lewis E. Cobb, Marblehead, Mass, assignors to Hygrade Sylvania Corporation, Salem, Mass., a corporation of Massachusetts Application January 28, 1931, Serial No. 511,702

3 Claims. (Cl. 91-45) This invention relates to spray guns and similar dent from an inspection of the drawing, that it apparatus for applying coating materials by the intercepts or cuts off sharply one edge of the fanspray method. shaped spray.

In using apparatus of this character it is a In using this apparatus to internally coat a common practice to protect parts of the work portion of an electric lamp bulb, as for example 0 adjacent to that against which the spray is dithe rounded bowl portion 2, Fig. l, the spray gun rected by covering such parts with paper, tape, or is inserted in the bulb in approximately the relathe like. In some cases, however, this expedient tionship illustratedv in Fig. 1, and the bowl is recannot be used satisfactorily, as for example, in volved about its own axis while the spray is diinternally coating relatively small articles such as rected against its inner surface. The shield 18 so electric lamp bulbs. controls one side of the spray that the coated area The present invention deals especially with terminates atafairly definite edge. Asufficiently these conditions. It aims to improve spraying clean line of demarcation thus is provided between equipment with a view to affording better control the coated and the uncoated areas to satisfy the 15 of the spray so that surfaces adjacent to those to demands of the trade. At the same time this rebe coated can be protected from the spray without suit is produced without using an internal covering the necessity of covering them with some protectfor the portions of the bulbs which are not to be ing material. coated. Usually the bulbs are heated during the The nature of the invention will be readily unspraying operation so that the coating dries very derstood from the following description when read quickly. in connection with the accompanying drawing; Some of the coating material intercepted by the and the novel features will be particularly pointed shield 18 will collect on the shield and run down out in the appended claims. to the lower edge where it tends to drop off. In

In the drawing, order to prevent this action the lower edge of Figure 1 is a perspective view of an apparatus the shield is bent or rolled over to form a trough embodying features of this invention; 21 extending along the lower edge, this trough Fig. 2 is a plan view of the spray nozzle shown serving to catch and hold the coating material in Fig. 1; that otherwise might drop from the edge of the Fig. 3 is a perspective View of the end portion shield. 30 of the nozzle and adjacent parts of the apparatus A somewhat different arrangement is illusshown in Figs. 1 and 2; and trated in Fig. 4 in which the spray gun is so Fig. 4 is a side elevation of a somewhat differmounted that its shank 13 occupies approximateent embodiment of the invention. 1y an upright position. This gun also is equipped Referring first to Figs. 1, 2 and 3, the apparatus with a shield 24, much like the shield 18, and se- 35 there shown comprises a spray gun 10 which incured to the shank 13 in the same manner. The

cludesacontrol lever or trigger l2,arelatively long shield tapers, with its larger end extending upshank 13, and a spray head or nozzle 14. The wardly, and its edges are rolled or turned inwardnozzle includes two air outlets 15, Fig. 3, located ly so that they catch and guide any drip into at opposite sides of another outlet 16 for the a tube 25 which extends along the shank 13 of 40 paint, lacquer, or other coating material, the two the spray gun and leads into an annular trough air outlets 15 being.directed toward each other or receptacle 26 secured. to the gun at the lower and toward the paint-outlet 16. So far as these end of the shank 13. Another tube 27 leads the features are concerned the spray gun is of a comdrip from this receptacle to any desired point of mon commercial type and it may be constructed, discharge.

45 arranged and operated in the usual manner. This shield operates to cut off the edge of the A gun of this construction produces a fan-like spray in the same manner as does the shield 18 spray which scatters considerably at the edges. and thus to afford much better control of the In order to cut off the spray more sharply, the coating material at the edge or margin of the spray gun shown is equipped with a shield 18 coated area. K

50 which may conveniently be made of sheet metal In addition to using a shield like those shown 5 and preferably includes asplit clamp 19 by means at 18 and 24 which control the spray at one side of which it is detachably secured to the shank 13 only, a second shield such as that indicated at of the spray gun, the split portions of the clamp 28, Fig. 4, can be used to control or cut off;- the being secured together by a screw or bolt 20. This opposite side of the spray, and such a device may 55 shield is so shaped and positioned, as will be evibe used eitheralone or in conjunction vf'th a all shield like that shown at 18 or 24. The shield 28 is provided with a split clamp 30 to secure it detachably to the shank 13 of the spray gun.

Such an arrangement as that shown in Fig, without the shield 28, is particularly adapted for use in a machine for internally coating lamp bulbs to produce a so-called white bowl efiect. The shield 28 may be used without the shieldZ in internally skirt coating a lamp bulb, while the two may be used together where it is desired to coat a band only of the skirt or cone of the bulb.

While we have herein shown and described preferred embodiments of our invention, it will be understood that the invention may be embodied in other forms and that the apparatus may be used for other purposes without departing from the spirit or scope of the invention.

Having thus described our invention, what we desire to claim as new is:

1. In an apparatus for applying coating ma terial to the inner surfaces of electric lamp bulbs, the combination of a spray gun constructed to be inserted in an electric lamp bulb through the. neck thereof, said gun having a nozzle adapted to produce a fan-like spray and to direct said spray laterally away from said gun and against the inner walls of the bulb, a shield mounted on said gun and shaped and positioned to cut off one edge of said spray and to combine the coating to a predetermined area having a sharply defined boundary, and a trough at one edge of said shield for catching any liquid which may run down face of the shield.

2. In an apparatus for applying coating material t0 the inner surfaces of electric lamp bulbs, the combination of a spray gun constructed to be inserted in an electric lamp bulb through the neck thereof, said gun having a nozzle adapted to produce a fan-like spray and to direct said spray laterally away from said gun and against the inner walls of the bulb, a shield mounted on said gun for cutting ofi one edge of said spray and to confine the coating to a predetermined area having a sharply defined boundary, and means for conducting liquid which collects on and runs down the face of the shield backwardly along the shank of said gun.

3. In a device for applying a coating having a sharply defined boundary to the inner surface of a bulb having an elongated neck and a spherical bowl portion, the combination of a spray gun having an elongated shank, a discharge end for insertion through the neck portion of the bulb, said gun having a discharge nozzle inclined to said shank for producing a fanlike spray mainly at an angle to the longitudinal axis of the bulb and against the inner wall of said bowl portion, and a shield carried by said gun laterally adjacent said nozzle for intercepting the spray to confine it to a predetermined area on the inner surface 

